The broad, long-term objective of the current application is to reduce the prevalence of alcohol abuse and alcohol-related negative consequences in college student social organizations, through the development of effective prevention programs. This research is an extension of successful brief motivational enhancement approaches to the prevention of alcohol-related problems with individuals. The specific aims of the study are (1) To test the efficacy of a combined group and individual motivational enhancement approach to the prevention of alcohol problems in fraternity and sorority pledge (freshman) class members; (2) to test the transfer of program effects within these organizations to members not directly targeted by the intervention; and (3) to evaluate changes in perceived norms for alcohol consumption and motivation to change drinking behavior as mediators of program effectiveness. To accomplish these objectives, 12 fraternities and 12 sororities will be randomly selected from all houses on the University of Washington Campus. Houses will be stratified by gender, then randomly assigned to one of two conditions: prevention programming (n=6 fraternities, 6 sororities) or assessment-only control (n=6 fraternities, 6 sororities). Pledge (freshman) class members of houses assigned to the prevention condition (n=210 subjects, 90 freshman men, 120 freshman women) will receive individual motivational interviews during Winter quarter of their first year at the University, and will also receive graphic feedback summarizing their progress in the Winter quarter of their sophomore year. In addition, the entire membership of houses assigned to the prevention condition will be provided with a group motivational feedback program in the Winter quarter of the first year, which will include the provision of aggregate feedback tailored to the specific risks of their organization and developed in conjunction with house leaders. A follow-up feedback program will be provided during Spring quarter of the first year. Pledge class members will be followed up for four years, to assess short- and long-term program efficacy. In addition, organizational response to the intervention will be determined through assessment of two successive pledge classes in each house during the follow-up period.